1398731 has 2 divisors, whose sum is σ = 1398732. Its totient is φ = 1398730.

The previous prime is 1398721. The next prime is 1398737. The reversal of 1398731 is 1378931.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1398731 - 2⁶ = 1398667 is a prime.

It is a super-2 number, since 2×1398731² = 3912896820722, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1398737) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 699365 + 699366.

It is an arithmetic number, because the mean of its divisors is an integer number (699366).

2^1398731 is an apocalyptic number.

1398731 is a deficient number, since it is larger than the sum of its proper divisors (1).

1398731 is an equidigital number, since it uses as much as digits as its factorization.

1398731 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4536, while the sum is 32.

The square root of 1398731 is about 1182.6795846720. The cubic root of 1398731 is about 111.8350836031.

The spelling of 1398731 in words is "one million, three hundred ninety-eight thousand, seven hundred thirty-one".